Characterization of a gamma-glutamyl kinase from Escherichia coli that confers proline overproduction and osmotic tolerance.
AUTOR(ES)
Smith, L T
RESUMO
Mutation(s) in the proBA operon of Escherichia coli confers proline overproduction and enhanced osmotic tolerance in enteric bacteria (L. N. Csonka, Mol. Gen. Genet. 182:82-86, 1981; M. J. Mahan and L. N. Csonka, J. Bacteriol. 156:1249-1262, 1983). A glutamate-dependent ATPase assay was developed and used to determine proB-encoded gamma-glutamyl kinase activity in the absence of glutamate-gamma-semialdehyde dehydrogenase. This assay indicated that the feedback insensitivity of mutant gamma-glutamyl kinase was independent of glutamate-gamma-semialdehyde dehydrogenase. However, the capacity of glutamate-gamma-semialdehyde dehydrogenase from the osmotolerant mutant to interact with the kinase was altered in thermal stability, suggesting that mutations in both proB and proA may be required for osmotolerance.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=219301Documentos Relacionados
- Purification and characteristics of a gamma-glutamyl kinase involved in Escherichia coli proline biosynthesis.
- Transport of gamma-glutamyl amino acids: role of glutathione and gamma-glutamyl transpeptidase.
- Identification of a human gamma-glutamyl cleaving enzyme related to, but distinct from, gamma-glutamyl transpeptidase.
- Inhibition of gamma-glutamyl transpeptidase and induction of glutathionuria by gamma-glutamyl amino acids.
- Involvement of gamma-glutamyl peptides in osmoadaptation of Escherichia coli.